APA (7th ed.) Citation

John XXIII, P. (1963). Pacem in terris. Peace on earth; encyclical letter of His Holiness Pope John XXIII, with Study Club Outline. Glen Rock, N.J..

Chicago Style (17th ed.) Citation

John XXIII, Pope. Pacem in Terris. Peace on Earth; Encyclical Letter of His Holiness Pope John XXIII, with Study Club Outline. Glen Rock, N.J., 1963.

MLA (8th ed.) Citation

John XXIII, Pope. Pacem in Terris. Peace on Earth; Encyclical Letter of His Holiness Pope John XXIII, with Study Club Outline. Glen Rock, N.J., 1963.

Warning: These citations may not always be 100% accurate.